Truck tractor



FIG. 1 is a front elevational view of a truck tractor showing my new design.

FIG. 2 is a right side elevational view thereof.

FIG. 3 is a left side elevational view thereof.

FIG. 4 is a rear elevational view thereof; and

FIG. 5 is a top plan view thereof.

The characteristic feature of my design rides in the particular pattern of the color scheme on the surface of the truck tractor. 

The ornamental design for a truck tractor, substantially as shown and described. 